It’s impossible to prove a negative, but I’m rather sure there is nothing official that covers this. To that end, here are all the most likely sources across all of D&D to cover something like this, and how they don’t.
Note that numerous sources discuss how fiends all have names other than their “true name,” that they could use for this purpose. As ...
Dragon Magazine 278 (December 2000)
A Dwarven Lexicon (p44)
Many non-dwarven races also use the Dwarven alphabet, even if they use
different pronunciations and meaning for the characters. The gnomes,
longtime allies of the dwarves, adopted the Dwarven script ages ago to
facilitate communication in trade and their shared war against
goblinoids. Bugbears, ...
Oh, Very Very Yes
If you want some dead gods, come on down to the Avatar Trilogy, where Bane got Banedead, Bhaal rolled over, Myrkul went from being God of the Dead to dead of the god, and other such fun events. They're not the only ones - just some of the many who had themselves a very bad day during the Time of Troubles. Each one had the bad luck to be ...
TL;DR: it prefers to target ferrous metal
This is likely a hold-over from earlier editions, which had this text in the 2e Monster Manual entry for Rust Monster:
Rust monsters, being none too bright, stop pursuing a fleeing party for one round to devour metallic items, such as a handful of iron spikes, a mace or a hammer, if the party throws them behind. ...
Mordenkainen's Tome of Foes dedicates its fourth chapter (starting at p. 85) to the gith, expanding upon the material found in the Monster Manual. On page 87, under the heading "Only the Best Survive", it has the line:
Githyanki hatch from eggs.
Which is a fairly clear answer.
The explanation varies between editions of D&D
According to the AD&D 1st edition Players Handbook, wearing metal armor interferes with the druid's supernatural abilities, but merely carrying items made of metal does not:
The more powerful druidic spells, as well as their wider range of weaponry, make up for the fact that druids are unable to use any ...
It's the Dungeon Master's Guide
In this case the "Ultimate Book of the Master" is just a playful reference to the DMG - since that is, after all, the book meant for the "master" of the game. A lot of the published material of that era seems to refer to the DM's position and authority with a (possibly tongue-in-cheek) reverence which feels ...
You are correct that Tolkien is responsible for popularising the modern orc, although there are earlier references including in Beowulf, which is one of the oldest written works in English - albeit Old English - however, I'm sure you can find the orcish reference:
þanon untydras ealle onwocon
All evil progeny were born from him (Cain)
eotenas ond ylfe ond ...
They have diametrically opposed cultures
Hobgoblins, though generally opposed to most other races besides their fellow goblinoids, have been described as having a specific hatred of elves since the earliest editions of D&D, with the 1e Monster Manual noting that:
If elves are nearby, hobgoblins will attack them in preference to any other troops because ...
Svirfnebli is the plural noun / adjective for Svirfneblin
Let's switch your examples with Humans:
When the human guards ushered him in
Scores of humans rushed about their posts
That should make things more clear. It is confusing, the words are very similar, but "svirfnebli" is to "svirfneblin" what "elves"/"elven" ...
The Githyanki and Githzerai are both Gith
Mordenkainen's Tome of Foes details that the Githyanki and Githzerai are simply two factions of being a Gith:
But after they won their freedom, two factions among the gith disagreed on what kind of civilization they would forge.
The factions are mechanically described as sub-races of Gith, not as separate races. ...
All of them: Mordenkainen was and remains a Magic User
The use of schools of magic as a categorization or limitation for spell casters has an uneven history in D&D – Mordenkainen predates all of them. He was created as a 1st level Magic User in 1973 – before the game was first published. (Rob Kuntz, DM).
He was thus created well before AD&D 1e ...
Entirely different creatures united conquered under a common faith.
Volo's Guide to Monsters has some info on this in the section Goblinoids: The Conquering Host:
Maglubiyet is truly the Conquering God. He stiffens the spines of cowardly goblins. He rouses bugbears from their lazy slumber. He sets the thunderous step of hobgoblin legions. Maglubiyet takes ...
The 2e boxed set City of Splendors discusses the activities of this guild on page 43 of the second book, Who's Who in Waterdeep (it's #11 under "Roster of the Guilds"). It says, in part:
Salters, packers, and joiners are the professionals at preparing goods for shipping long distances. [...] Joiners make shipping crates out of finished lumber after the ...
Most of these characters go back to the early days of D&D
Iggwilv (aka Tasha) is a fictional wizard from the Greyhawk campaign setting for the Dungeons & Dragons roleplaying game. She was created by Gary Gygax.
She dates back to 1st edition.
The crime lord of Waterdeep was introduced with the Forgotten Realms boxed set.
There is not a direct in-lore answer to this that I am able to find. So the best I can do is a partial frame challenge and suggest you look at how this could be done by looking at history and even modern legal rules to establish your rules.
Here's what we know
Though devils all have common names, every devil above a lemure in station also has a true name ...
If it can understand morality enough to have an alignment, it can worship whatever deity it chooses to
This is a bit of a strange situation; in comments, you mention how its stats are as per the Monster Manual, so an Intelligence score of 3, but it is also Lawful Good.
RAW, generally beasts with an Intelligence of 3 or less are unaligned, which makes sense ...
In fifth edition, the description of liches does indeed suggest that they are specifically wizards. But... well... fifth edition has said a lot of really dumb things, in my opinion, on the subject of liches. Requiring a major artifact in The Book of Vile Darkness, forcing archdevils or demon princes to be involved in each individual lich is ridiculous, and ...
D&D orcs aren't related to elves, but it varies by campaign setting.
The origins of the orcs varies between campaign settings and sources, but it is most commonly asserted that they were simply created by Gruumsh, primary deity of the orcs in many worlds.
Unlike in Tolkien's works, D&D's orcs are not derived from elves. Gygax was eager to distance ...
You should still ask them.
If you are in a position to ask a dragon without being roasted, dragons are sentient persons and deserve as much respect as you would give any other person.
There may be cases where their gender identity does not match their biological sex, so you should ask politely to be sure.
I like the idea of a quest involving a dragon that's ...
You are most likely thinking of the Marut, a powerful construct/outsider (depends on the edition) that hunts those who cheat death, and has been in every edition since AD&D.
What they are like for each edition:
1e AD&D - In 1e, They are the most powerful variety of inevitables, and although only a little information is given, it is mentioned how '...
A lich is usually a wizard, but practically always a spellcaster.
Firstly, a DM can always invent or change elements in their own campaign. Perhaps a wizard's treacherous servant interrupted their lichdom ritual and stole the power for themselves.
However, a lich is defined as a wizard in the D&D 5e Monster Manual, and while the D&D 4e and 3.5 ...
Several resources refer to the Lady of Pain
...particularly in 2E's Planescape materials, the Planescape Campaign Setting being a good place to start. In The Cage: A Guide To Sigil has mentions as well. The novel Pages of Pain purpots to tell the most about her, though as is frequently noted - even by the book itself - it's full of lies and rumors rather ...
This is going to be a significantly long journey.
I'm not sure if your party realizes just how far it is from The Dalelands to Waterdeep. For reference, it's roughly 1,200 miles as the crow flies. Unfortunately, however, there is no direct travel route that takes you on a straight line from Shadowdale to Waterdeep. There's the Desertsmouth Mountains, the ...
They could take off their boots, but they don't
Redcaps are based on older myths from England, and in all of them they wear iron boots. D&D simply copied that part of the lore in and then attached some rules to it.
Redcap is depicted as "a short, thickset old man with long prominent teeth, skinny fingers armed with talons like eagles, ...
It really is going to depend on the setting, and what you as DM want to do with it. As far as official settings go, Eberron comes to mind:
From Eberron: Rising From the Last War, page 193, under "Dragons":
The dragons of Eberron aren't restricted in alignment — good red
dragons and evil gold dragons are equally common. Most dragons tend
My guess is that the author thought cordwainer was a synonym for ropemaker - a cord is a thin rope and the author mistakenly thought that cordwainer was a maker of cords rather than (leather) shoes. Inconceivable. If so, it’s a lesson to always check the dictionary before using unfamiliar words.
Given that sailmakers use canvas from hemp to make ...
It's a third edition concept which might exist only in a world's history.
Epic magic is an idea which dates to earlier editions of the game, and which isn't available to player characters in fifth edition (yet, at least). However, it is something which canonically existed in many worlds, such as the Forgotten Realms. How it exists or existed in a 5e campaign ...
The AD&D 2nd Edition Monstrous Manual gives more examples of oozes, from which we can draw some inferences. Oozes, slimes, and jellies are listed together (pg. 276-280.) Puddings have their own separate listing (pg. 297.)
Slimes are largely immobile and plantlike
As in 5th edition, green slime is a dungeon hazard, but here it appears with the more ...
There are no rules for Epic Magic in D&D 5e
As of writing this answer, no rules have been released for Epic Magic in the 5th edition rules. Elven High Magic isn't mentioned anywhere, and spells are officially between 0th and 9th level:
Every spell has a level from 0 to 9.
...the only exception to this is the artifact Book of Exalted Deeds which allows ...